Process of metallurgical treatment



Oct. 6, 1931.

C. THURNEYSSEN PROCESS OF METALLURGICAL TREATMENT Filed Feb. 19, 1927 in re/17br Patented Oct. 6, 1931 UNITED" STATES PATENT OFFICE cnnrsrrenrnunnnrssnn, or mars, rmcn' nssrenon ro socmrn Ln'nroxnn, or

' rams, FRANCE rnoonss or mn'rmunercar. rana'nrnnr Application filed February 19, 1927, Serial No. 169,494, and in France February Q8, 1928.

fortreating alloys of non-volatile metals, oneof which is more oxidizible than theother and particularly to the treatment, of ferro-alloys vantage for the known converter process 5. corresponding to the'above conditions for .the purpose of enriching them by removingpart of the iron. Y I

The said process consists essentiall in spraying the metal or alloy by ajet 0 gas 0 delivered into a suitable atmosphere.

The invention further relates to an apparatus comprising in combination suitable means for projecting the metal or alloy in a stream or jet, a noz e for delivering a strong blast .5 of a suitable gas u on the metallic jet, and

a chamber traverse by a suitable currentof gas. The said invention has chiefly for its ob ect the removal of iron from its alloys, in which I the iron is more readily oxidized thanthe T other metals in the alloy. For such purposes I proceed in the following manner. r The drawing illustrates the process diagrammatically. 55 The iron alloyiis poured in a thin stream in an oxidizing atmosphere, and it is sprayed by any suitable gas. The fine metallic drops are thus partially oxidized, and the resulting powdered substance is melted in a furnace tol0 gether with adequate scorifyin substances so as to separate the oxide of iron rom the metal which is to be obtained.

The metal delivered from the melting furnace is poured in a stream having a few millimeters diameter, into a chamber or pit with metallic walls, having several meters length and several square meters cross section, in

' which is circulated a strong blast of oxidizing gas or air. After a few centimeters of free fall, the metallic jet is broken up by a powerful jet ofcompressed as which sprays the metal into fine drops, an these drops will take firespontaneously in contact with the oxidiz-' ing gas or air. The combustion. is completed withina very short time,and all the iron is oxidized. When cold, the'met'al is'mixed with a silicious substance such as sand or even a silicious mineral substance. The whole is melted in a furnace, and the oxide of iron will thus produce sili- 4 the atmosphere therein.

cates'and will form a slag; this is separated fromthe metal sought for, and the metal is cast into ingots.

My said process can be substituted to ad-. which is in many cases diificultof application 55 by reason of the high temperatgire required for the melting of the iron alloys, or due to the insuflicient heat from. the combustion of the iron, or. to the rapid wear of the converter lin-.

It should be noted that in its-various applications the said process may comprise, among others,- the followin modifications: 1. The compresse gas which is employed for spraying purposes may be carbon dioxide, nitrogen, or like gases under pressure.

2. .The walls of the pulverizing chamber, instead of being metallic, may be, forjexamj ple, cement mortar or reinforced cement 7 (concrete); t 3. In the case of treating ferro-alloysthe metallic powder obtained after pulverization is collected, then treated in a second operation to'carry itto the desired degree .of oxida- 76' tion. If oxidation has been insuflicient in the pulverization 's'tep'the powder is roasted. If, on the contrary, oxidation is exaggerat-' ed the powder collected is melted in the chambers "after .pulverization and metal not yet pulverized is added. 4. In the same-treatment, the oxide of iron may be scorified without the use of a scori ing substance, such as sand or mineral su stance, by melting the material in an electric furnace; for example, and herein the slag required oxidizing or like atmosphere may be delivered-by oneor more blowers or a venti-' lating chimney, or it may be withdrawn by the suction which may be created by the spraying'nozzle itself. u

6.. The thickness of the stream of liquid metal which can be properly oxidized by the 95' spraying processdepends chiefly upon theamount and the pressure of the gas employed for the spraying, and also upon' the size of the spraying chamber and the composition of Example A.A ferro-nickel containing 60% of nickel and 40% of iron is obtained by melting garnierite electrically. This ferro-nickel is pulverized and remelted accord ing to the process claimed, and we thus obtain a metal containing no more than 5 to 6% of iron. Although the process permits of further considerably reducing this iron con; tent, we do not, however, exceed this limit in practice to reduce the loss of nickel in the slag. The deferrized ferro-nickel that is, the nickel from which the iron has een removed) is then refined by electrolysis.

Having now particularly described and ascertained the nature of my invention and in what manner the same is to be performed, I declare that what I claim is:

1. Process for separating out the iron of ferro-nickel, ferro-cobalt and the like, consisting in melting the alloy to be purified, carrying it to a temperature of about 1500, appreciably above the fusion temperature of said alloy, pouring said liquid alloy in the form of a liquid thread, atomizing said liquid in an. oxidizing atmosphere through a jet of gas under pressure into liquid droplets so as to oxidize the iron of these droplets durin their'passage through the air, collecting sai solidified and oxidized droplets, remelting said droplets, carrying the degree of oxidation of the bath to the desired extent and separatingthe non-oxidized parts from the oxidized parts. I

2. Process for separating out'the iron of ferro-nickel, ferro-cobalt and the like, consisting in melting the alloy to be purified,

carrying it to a temperature of about 1500, appreciably above the fusion temperature of said alloy, pouring said liquid alloy in the form of a liquid thread, atomizing said liquid 'in an oxidizing atmosphere through a jet of gas under pressure into liquid droplets so as to oxidize the iron of these droplets durin their passage through the air, collecting said solidified and oxidized droplets, remelting said droplets with the alloy to be purified and carrying the oxidation to the desired extent and separating the oxidized from the non-oxidized parts.

' In testimony whereof, I have signed myname to this specification at Paris this 2nd day of February, 1927. I

CHRISTIAN THURNEYSSEN. 

